A study by the Children’s Oncology Group (COG) reported that 5-year survival for acute lymphoblastic leukemia (ALL) among children treated through COG clinical trials increased from 83.7% during the period 1990-1994 to 90.4% in the period 2000-2005. The improvements in survival were observed among all children over age 1 regardless of age, sex, ethnicity, or subtype of ALL. This analysis, which is the largest study to date of ALL survival, showed similar gains in 10-year survival. The findings were published recently in the Journal of Clinical Oncology.1
“New drugs and new drug combinations have increased survival rates and helped children live longer and better, and we continue to refine these therapies. Nevertheless, we still have important work to do to help the remaining 10% of patients who don’t survive,” said lead author Stephen Hunger, MD, Professor of Pediatrics at the University of Colorado School of Medicine and Director of the Center for Cancer and Blood Disorders at Children’s Hospital Colorado.
Dr. Hunger and his colleagues analyzed long-term survival among 21,626 individuals who were treated for ALL as children or adolescents (infancy to age 22) in COG clinical trials between 1990 and 2005, dividing this time period into three “eras” that included similar-sized patient groups to examine changes in 5- and 10-year survival over time.
In addition to the gains in 5-year survival, they found that 10-year survival increased from 80.1% between 1990-1994 to 83.9% in 1995-1999. Survival improved significantly in all of the following subgroups: children ages 1-9 years; 10 years and older; 15 years and older; males and females; whites, blacks, and other races; Hispanics, non-Hispanics, and persons of unknown ethnicity; those with B-precursor ALL and T-cell ALL; and those with standard-risk or high-risk disease
Among infants (age 1 and younger), however, 5-year survival changed little between 1990-1994 (52.1%) and 2000-2005 (50.3%), while the causes of death changed considerably. Death rates from ALL relapse or progression decreased from 43% in 1990-1994 to 27.2 % in 2000-2005, while the incidence of treatment-related deaths increased from 3.9% to 13.9% during this period.
Dr. Hunger emphasized that these data represent the advances that can be achieved against cancer through rigorous clinical trials. “Today, more than half of all children with cancer are treated through clinical trials, compared to less than 5% of adults with cancer,” he said. “Without a doubt, more and more children and older adolescents with leukemia are cured today because of the patients and parents who were willing to participate in clinical research.”■
1. Hunger SP, Lu X, Devidas M, et al: J Clin Oncol. March 12, 2012 (early release online).